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The harvesting of wood species intended for energy production is one of the critical steps for the establishment of an economically viable supply chain. The review examines the state of the art of the main systems for collecting the short rotation coppice (SRC) by referring to poplar ( Populus spp.), one of the main energy species for southern Europe. Starting from the early experiences of willow ( Salix spp.) in Sweden, over time two approaches have established: the cut-and-chip and the harvest-and-storage system. In the work, the pros and cons of the two systems are analyzed and their efficiency compared, giving also some indication about the next evolution of the machines. Emerging systems showing an interesting future potential as bales production or the development of small-scale tractor-powered harvesters are also described. Finally, some economic considerations on differences between harvesting cost for the cut-and-chip and harvest-and-storage system are reported. [ABSTRACT FROM AUTHOR]

Abstract: Tomato (Lycopersicon esculentum L.) fruit are an important source of antioxidant (mainly pigment) compounds, as well as lycopene, β-carotene, ascorbic acid and polyphenols. Differentiation of the final product in the market requires an accurate evaluation of these value-adding compounds. Because of this, we have undertaken a comparison of the spectral characterisation of the tomato fruit surface pigments from the immature to over-ripe stage, using spectroscopy techniques based on visible fluorescence emission upon excitation in the same or ultraviolet spectral regions. The aim was to verify the spectral band for optimal conditions for fruit harvesting using non-destructive techniques. The pattern of pigment composition changed markedly during ripening and showed progressive disappearance of chlorophyll with a concomitant increase in carotenoids until the fully ripe stage. The main fluorescence spectral features belonging to anthocyanins, flavonoids, carotenoids and chlorophyll a after excitation of skin tomato pigments at different laser wavelengths was identified. In comparing, the fluorescence spectral ratios at the excitation wavelength λ exc =266nm, significant differences were obtained for the spectral ratios of chlorophyll/flavonoids and carotenoids/chlorophyll. Positive correlation coefficients were found for the carotenoids/flavonoids (0.780) ratios and negative ones for the carotenoids/chlorophyll ratios (−0.513). Analysis of fluorescence resulted in determination of the most useful laser radiation for remote non-invasive measurements with laser-induced fluoresence (LIF): for the ripening stage, λ exc =266nm was the optimal laser wavelength, since the induced fluorescence spectra obtained appeared to differ with the physiological stage of the fruit. [Copyright &y& Elsevier]

Aim of the work was to characterize the peels of novel tomato lines (with red, orange, pink, black-red, and dark-red fruit) for the content of bioactive substances and for some parameters linked to no-food use. Chlorophyll, polyphenols, and carotenoid content, energy value, theoretical biochemical methane potential (TBMP) through stochiometric method were evaluated. The peel color mirrored a different content of the bioactive substances: the dark-red fruits showed a significant increase of the carotenoid content, while the peel of the black-red fruits had the highest values of polyphenols. The preferential accumulation of functional compounds influenced the values of the other parameters. The colored lines compared to the red-fruited control (C) contained less carbon and hydrogen mass fractions and, subsequently, a lower LHV. This, in turn, led to a substantial difference in the estimation of the TBMP. Interestingly, this production was higher in the highly pigmented line, which contained a gene present in some high-lycopene commercial varieties. A circular production model for exhaustive use of peel is proposed. • Wastes of tomato processing (peels mainly) may be re-used for additional process. • Peels of new tomato lines with red, yellow or black color were analyzed. • Carotenoids and polyphenols content varied greatly depending by the peel color. • The content of the antioxidant compound affected in turn the potential BMP. • Once extracted the biocompounds peels may enter in the anaerobic digestion route. [ABSTRACT FROM AUTHOR]

We investigate the existence (or lack thereof) of the chiral magnetic effect (CME) in the framework of finite temperature field theory, studied through the path integral approach and regularized via the zeta function technique. We show that, independently of the temperature, gauge invariance implies the absence of the effect, a fact proved, at zero temperature and in a Hamiltonian approach, by Yamamoto. Indeed, the effect only appears when the manifold is finite in the direction of the magnetic field and gauge-invariance breaking boundary conditions are imposed. We present an explicit calculation for antiperiodic and periodic boundary conditions, which do allow for a CME, since only 'large' gauge transformations are, then, an invariance of the theory. In both cases, the associated current does depend on the temperature, a well as on the size of the sample in the direction of the magnetic field, even for a temperature-independent chiral chemical potential. In particular, for antiperiodic boundary conditions, the value of this current only agrees with the result usually quoted in the literature on the subject in the zero-temperature limit, while it decreases with the temperature in a well-determined way. [ABSTRACT FROM AUTHOR]

Pruning residues can provide a significant amount of biomass despite being rarely used as a renewable sources to replace fossil fuels. Exploiting such residues entails creating a sustainable and cost-effective supply chain in which the harvesting and initial processing of the residues play a crucial role. The study is a detailed and accurate survey of the harvesting technologies available in Europe for harvest pruning. After defining the main harvest technologies and the distribution of manufacturers in Europe, the survey details the main groups of implements: shredders, chippers and balers. For each group, the most important configurations are discussed, together with the main characteristics of the machine. Some of the main innovations are detailed (modular machines, non-stop balers, densification of the biomass) which can improve the quality of the product and the economic sustainability of the chain. [ABSTRACT FROM AUTHOR]

We obtain, through ζ function methods, the one-loop effective action for massive Dirac fields in the presence of a uniform, but otherwise general, electromagnetic background. After discussing renormalization, we compare our ζ function result with Schwinger’s proper-time approach. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

We establish some properties of the zeros of sums and differences of contiguous Bessel functions of the first kind. As a by-product, we also prove that the zeros of the derivatives of Bessel functions of the first kind of different orders are interlaced the same way as the zeros of the Bessel functions themselves. As a physical motivation, we consider gated graphene nanodots subject to Berry-Mondragon boundary conditions. We determine the allowed energy levels and calculate the mean charge at zero temperature. We discuss its dependence on the gate ( chemical) potential in detail and also comment on the effect of temperature. [ABSTRACT FROM AUTHOR]

The major sex pheromone compound of the spotted tentiform leafminer, Phyllonorycter blancardella (F.) (Lepidoptera: Gracillariidae), from Ontario, Canada, was identified as (10 E)-dodecen-1-yl acetate ( E10-12:Ac) using chemical analysis and field trapping experiments. The minor compounds (10 E)-dodecen-1-ol ( E10-12:OH) (4.6%), dodecan-1-ol (12:OH) (2.3%), and (10 Z)-dodecen-1-yl acetate ( Z10-12:Ac) 1.6% were also identified. The dienic acetate (4 E,10 E)-dodecadien-1-yl acetate ( E4, E10-12:Ac), a compound reported to be attractive to P. blancardella, was not found in the glands of this population. A two-component blend of the major and one of each the three minor compounds, in ratios similar to those found in the sex pheromone gland, did not increase the attractiveness of traps baited with synthetic pheromone. The minor compounds E10-12:OH and 12:OH were not attractive to P. blancardella when tested individually. Z10-12:Ac was attractive to P. blancardella, although traps baited with this compound captured only 2% of the moths that were captured in traps baited with the main compound. A four-component blend of the major and each of the three minor compounds (100 : 1 : 1 : 1) was not more attractive than the major compound alone. The related species Phyllonorycter mespilella was captured in traps baited with E10-12:Ac. [ABSTRACT FROM AUTHOR]

We study the problem of a Dirac field in the background of an Aharonov-Bohm flux string. We exclude the origin by imposing spectral boundary conditions at a finite radius then shrinked to zero. Thus, we obtain a behavior of the eigenfunctions which is compatible with the self-adjointness of the radial Hamiltonian and the invariance under integer translations of the reduced flux. After confining the theory to a finite region, we check the consistency with the index theorem, and evaluate its vacuum fermionic number and Casimir energy. [ABSTRACT FROM AUTHOR]

Examines the computation of functional determinant for a Dirac operator in the presence of an Abelian gauge field on bidimensional disk. Introduction of the global boundary conditions; Connection between calculated determinant and index theorem; Evaluation of the determinant.

The use of a biorthogonal basis for continuous wavelet transformations is explored, thus relaxing the so-called admissibility condition on the analyzing wavelet. As an application, the eigenvalues and corresponding radial eigenfunctions of the Hamiltonian of relativistic hydrogen-like atoms are determined. [ABSTRACT FROM AUTHOR]

This paper evaluates the determinant of a Dirac-like operator, for a system of fermions confined to a region of two-dimensional Euclidean space and subject to bag-like boundary conditions. In the framework of the ζ-function regularization method, use is made of Seeley’s developments for the resolvent of such operators. A relation is derived between the Green’s function and the finite part of the diagonal element of the kernel of the power z of the operator for z=-1, which amounts to having information about the whole Seeley’s series. [ABSTRACT FROM AUTHOR]

Weather extremes and extreme climate events, like late spring frosts, are expected to increase in frequency and duration during the next decades. Although spring phenology of European beech is well adapted to escape freeze damages on longer time scales, the effects of occasional late spring frosts (LSF) are among the main climatic damages to these forests to such an extent that they limit beech distribution and elevation range, especially at its southern margin. The aim of this work was to evaluate the short-term effects of two consecutive LSF events occurred in 2016 and 2017 in Italy on the beech forest vegetation activity. Remotely sensed land surface temperature (LST) data were used to detect the pixels where LSF occurred, while enhanced vegetation index (EVI) data were used to quantify LSF effects by computing a spring vegetation activity anomaly index (sAI). In 2016 and 2017, the LSF covered, respectively, about 29% and 32% of the total Italian beech-dominated area. The two LSF widely differed in their spatial patterns and their effects. In 2016, the pixels belonging to the sAI classes with the highest spring anomalies were also those where prolonged LSF occur, while, in 2017, the pixels belonging to the highest sAI classes were those that underwent the shorter (but probably more intense) LSF events. Under scenarios of increased frequency risk of repeated LSF, the proposed methodology may represent an automatic and low-cost tool both for monitoring and predicting European beech growth patterns. [ABSTRACT FROM AUTHOR]

The growing demand for biomass for energy use has led equipment manufacturers to focus their attention on the management of pruning wastes and on finding solutions for recovering such a huge amount of biomass. The first attempt consisted of adapting mulchers, which were used to incorporate these wastes into the soil; interest later shifted towards chippers and balers, which were able to produce a high-grade fuel. Two innovative prototypes for pruning waste collection were developed within the EuroPruning Project: a baler (PRB 1.75) designed by PIMR research institute (Poland), and a chipper (PC50) designed by the machine manufacturer ONG s. n.c. (Italy) with the scientific support of the CREA-IT institute (Italy). The main goal was to design special machines to harvest multiple types of pruning wastes from permanent crops and to build a sustainable and cost-effective supply chain. Both prototypes showed encouraging results. Their performances were largely comparable with those reported for similar machines, showing values of losses ranging from 36.2 to 46.2% and a maximum productivity of 2.80 (PC50) and 3.03 t fm h −1 (PRB1.75). Moreover, the particle size distribution in the feedstock produced by the chipper PC50 complies with the international standard for the commercial category P45. This study reports on the performance of both prototypes and the quality of the product obtained during the preliminary harvest-pruning tests carried out in vineyards and in peach and apple orchards. [ABSTRACT FROM AUTHOR]

One of the main constraints hindering the cultivation of fiber sorghum, which produces a substantial amount of fermentable biomass, is the lack of an efficient harvesting method. The anatomical structure of the fiber sorghum plant makes conditioning the plants difficult, resulting in increased losses, diminished product quality, and increased harvesting costs. The purpose of this study is to investigate an alternate harvesting method to improve the shelf life of sorghum biomass and thereby reduce the costs of harvesting sorghum. A prototype of a rear tractor-mounted mower-conditioner was designed, built, and tested over two years (2007-2008). The machine was able to mow and vigorously condition each plant in separated single rows. The conditioner consisted of two counter-rotating rollers placed lengthwise in a forward direction, which fractured and crushed the stalks, providing a remarkable improvement in work quality compared with current methods. The prototype achieved a significant reduction in drying times compared to other systems and extended the harvest window, thus eliminating one of the main obstacles to a wider cultivation of fiber sorghum. [ABSTRACT FROM AUTHOR]

We examine the local super trace asymptotics for the de Rham complex defined by an arbitrary super connection on the exterior algebra.We show, in contrast to the situation in which the connection in question is the Levi-Civita connection, that these invariants are generically non-zero in positive degree and that the critical term is not the Pfaffian. This article is part of a special issue of Journal of Physics A: Mathematical and Theoretical in honour of StuartDowker's 75th birthday devoted to 'Applications of zeta functions and other spectral functions in mathematics and physics'. [ABSTRACT FROM AUTHOR]

Abstract: Antiepileptic drugs (AEDs) are commonly prescribed for a wide range of disorders other than epilepsy, including both neurological and psychiatric disorders. AEDs play also a role in pharmacological management of neuropathic pain. Central post-stroke pain (CPSP) is a disabling morbidity occurring in 35% of patients with stroke. The pathophysiology of CPSP is not well known but central disinhibition with increased neuronal excitability has been suggested. AEDs include many different drugs acting on pain through several mechanisms, such as reduction of neuronal hyperexcitability. To our knowledge conclusive evidence has not been published yet. The aim of this review is to delineate efficacy and safety of AEDs in CPSP. [Copyright &y& Elsevier]

Background/Aims: Besides antioxidant vitamins and minerals, fruits and vegetables contain flavonoids and related phenolics. The biological activities of these polyphenols have become well known in recent years evidencing their beneficial effects on human health. In this context, the characterization of the flavonoids present in tomatoes is of great interest. Thus the polyphenol pattern (including flavonols, flavanones and cinnamate derivatives), lycopene and Β-carotene concentrations and the total antioxidant activity (TAA) of the phenolic fraction from different tomato lines and cultivars have been determined. Methods: The characterization was obtained by means of spectrophotometry and HPLC analyses. Results: Mean values for single flavonoids were 0.68 ± 0.16 for naringenin, 0.74 ± 0.12 for rutin and 0.32 ± 0.06 for a rutin-pentoside. Mean total polyphenol content was 13.15 ± 1.15 mg/100 g and mean TAA value was 1.3 ± 0.10 mmol/g. The obtained TAA values resulted in good accordance with the total polyphenol content (R 2=0.7928). The main phenolic acids were chlorogenic (mean ± SE 0.20 ± 0.03) and caffeic acid (mean ± SE 0.03 ± 0.01). Mean levels of lycopene and Β -carotene were 5.38 ± 0.90 and 1.18 ± 0.40 mg/100 g, respectively. Conclusions: Almost all the lines characterised by low carotenoid content produce high levels of polyphenols, and consequently have the most powerful antioxidant potential. [ABSTRACT FROM AUTHOR]

It is shown that a regularized determinant based on Hilbert’s approach (which we call the ‘‘p determinant’’) of a quotient of elliptic operators defined on a manifold with boundary is equal to the ‘‘p determinant’’ of a quotient of pseudodifferential operators. The last ones are entirely expressible in terms of boundary values of solutions of the original differential operators. It is argued that, in the context of quantum field theory, these boundary values also determine the subtractions (i.e., the counterterms) to which this regularization scheme gives rise. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Preoperative intra-aortic balloon pumping (IABP) improves the results of complex coronary surgery. However, its insertion may be harmful or contraindicated in cases of severe and diffuse atherosclerosis of the descending aorta and peripheral arteries. We sought to evaluate the efficacy and safety of transbrachial insertion of the new 7.5-Fr IABP to support a severely ill patient with eggshell distal aorta and femoro-iliac arteries undergoing coronary artery bypass grafting (CABG). DESIGN: Case report. SETTING: An 18-bed adult cardiac surgery unit at a university hospital. PATIENT: A 68-yr-old man with ongoing unstable angina, left main disease, and eggshell calcification in the abdominal aorta and iliaco-femoral arteries, needing IABP for CABG. INTERVENTION: Percutaneous sheathless right transbrachial insertion of 7.5-Fr IABP, followed by CABG. MEASUREMENTS AND MAIN RESULTS: Fluoroscopy and chest radiograph were used to confirm the exact position of the IABP, in the preoperative and postoperative time, respectively. A digital pulse oximeter was applied to monitor distal perfusion. Anticoagulation consisted of nadroparin 4000 IU daily until the second postoperative day, followed by 150 mg of aspirin daily thereafter. Transbrachial IABP support allowed uneventful CABG and postoperative course, without IABP-related complications. Pulse oximetry demonstrated constant good values, the radial artery pulse was always present, and the hand appeared constantly warm. IABP was withdrawn 20 hrs following surgery, and the patient was discharged home on the ninth postoperative day. CONCLUSIONS: The miniaturization of IABP, with the recent introduction of a 7.5-Fr balloon catheter, opens the door for the safe, effective transbrachial method of insertion in patients with severe peripheral atherosclerosis. [ABSTRACT FROM AUTHOR]